Package: smsncut
Type: Package
Title: Optimal Diagnostic Cutoff Selection under Scale Mixtures of
        Skew-Normal Distributions
Version: 0.1.0
Authors@R: c(
    person("Renato", "de Paula",
           email = "rrpaula@ciencias.ulisboa.pt",
           role = c("aut", "cre"),
           comment = c(ORCID = "0000-0002-5835-5918")),
    person("Helena", "Mouriño",
           role = "aut"),
    person("Tiago", "Dias Domingues",
           role = "aut"))
Description: Implements a parametric decision-theoretic framework for
        optimal diagnostic cutoff selection under the family of scale
        mixtures of skew-normal (SMSN) distributions, including the
        skew-normal (SN) and skew-t (ST) models as special cases. The
        optimal cutoff is defined by minimising a weighted
        misclassification risk that incorporates disease prevalence and
        asymmetric costs, leading to a likelihood-ratio equation that
        generalises the Youden criterion. Under a monotone likelihood
        ratio condition, existence, uniqueness, and global optimality
        of the cutoff are established. Asymptotic normality and a
        closed-form plug-in variance estimator are provided via the
        implicit function theorem and the multivariate delta method.
        Tools for model fitting, cutoff estimation, confidence
        intervals, the local identifiability diagnostic, and Monte
        Carlo simulation are included. The methodology is described in
        de Paula, Mouriño, and Dias Domingues (2026)
        <doi:10.48550/arXiv.2605.07829>.
License: GPL-3
Encoding: UTF-8
Depends: R (>= 4.1.0)
Imports: sn (>= 2.0.0), numDeriv (>= 2016.8-1)
Suggests: testthat (>= 3.0.0), knitr, rmarkdown
VignetteBuilder: knitr
NeedsCompilation: no
Packaged: 2026-07-04 17:24:49 UTC; root
Author: Renato de Paula [aut, cre] (ORCID:
        <https://orcid.org/0000-0002-5835-5918>), Helena Mouriño [aut],
        Tiago Dias Domingues [aut]
Maintainer: Renato de Paula <rrpaula@ciencias.ulisboa.pt>
Config/roxygen2/version: 8.0.0
Repository: https://cran.r-universe.dev
Date/Publication: 2026-05-19 08:50:02 UTC
RemoteUrl: https://github.com/cran/smsncut
RemoteRef: HEAD
RemoteSha: df95c3f1321c3d9a33b2a0582fae0f6b1bc5c401